To cancel your ChatGPT subscription, you need to do so through the same channel...

https://telegra.ph/How-Do-I-Cancel-ChatGPT-Plus-if-I-Paid-on-the-Website-07-12

To cancel your ChatGPT subscription, you need to do so through the same channel you used to subscribe—whether that’s the web via Stripe, Apple, Google Play, Business, or API